Combined typewriting and computing



' April 17, 1934. H PI MAN 1,955,606

COMBINED TYPEWRITING AND COMPUTING MACHINE Filed Feb. 23, 1932 EIGJ.

INVENTOR: 45 W M ATTORN- Patented Apr. 17, 1934 UNITED STATES PATENTOFFICE COMBINED TYPEWRITING AND COMPUTING MACHINE Application February23, 1932, Serial No. 594,49

9 Claims.

cient functioning of such devices in a typewriter in which computingregisters may be used and caused to be operated by strokes ofnumeral-keys. For correct operation of such registers, it is necessarynot only that the key-stroke be completed in both directions, but thatWhere a full-stroke device is used, it is very desirable that there bevery little backlash in the register-operating portion of either thedown or the up stroke.

One of the aims of the invention is to provide a set of full-strokeracks which can be mounted as a unit in the combined typewriting andadding machine, and also to provide readily accessible and easilycontrollable means for setting said unit at difierent elevations orpositions, so as to compensate for slight differences in manufacture indiiferent kinds of machines in this class.

According to the present invention, a full-stroke rack of simple form isemployed in which teeth finely spaced to minimize the backlash may read-,ily be out, said teeth co-operating with a doublearmed pawl pivoted tothe key-lever to check untimely reversal of either the up or downkeylever stroke. It is also desirable that for convenience of assemblingand maintenance, the

racks be mounted stationary relatively to the keystrokes, such mountingof the racks being accomplished in the present invention by simple andinexpensive devices which also permit fine adjustment of the racks inthe direction of keylever strokes, the racks being simple punchedblanks, and being formed for easy attachment to said mounting, and foreasy removal to facilitate inspection or replacement. It will beapparent, however, that material benefits may be derived from otherfeatures of the invention irrespective of whether it is the rack that isstationary with respect to the key-stroke or whether it is the pawl thatis stationary.

For positively checking untimely reversal of the key-lever stroke, it isdesirable that the rackteeth be of suitable form to engage and hold thepawl positively during such checking. Tothis end, a saw-tooth form ispreferably used, and two series of teeth are cut in the rack, one arm ofthe key-lever pawl being engageable with one series, and the other armof said pawl being engageable with the other series, the pawl-armsextending to opposite sides of the pawl-pivot, and substantially in thedirection of the keystrokes. As viewed in profile, the saw-shaped teethin one series are reversed with respect to the saw-shaped teeth in theother series, so that the saw-tooth form of each series may be effectivewith the pawl-arm with which it co-operates. A further feature of theimproved full-stroke rack is a single two-way pawl-shifting cam formedon said rack between the two series of pawl-teeth, said cam beingeffective to engage either one of the pawl-arms. The two series ofrack-teeth and the intermediate cam form a profile which in itself iscomplete to coact with the pawl-arms and to effect the shifting of thepawl, and which profile, including finely spaced teeth, may be cheaply,yet accurately, machined by a form-milling cutter, broaching device orother suitable tool. Blanks from which the racks are made are simplepunchpress stampings.

Each key-lever Whose strokes it is desired to control is provided withone of the novel fullstroke racks, and one of the two-armed pawls ispivotally mounted on the side of the key-lever, so that the rack mountedadjacent to the keylever and extending in the direction of key-strokemay coact with said pawl. A suitable detentdevice for the pawl is alsocarried by the keylever and co-operates with the rack-cam to shift thepawl at the extremities of the key-strokes, said detent-device beingalso effective to hold the pawl in either of the positions into which itmay be shifted to co-operate with one or the other series of rack teeth.

A difficulty that arises in machines in which the master-wheel of theadding mechanism is rotated by the key, and wherein the master-wheelcomes to rest before the key has driven the typebar to the platen, andwherein the full-stroke rack ceases to function as soon as themasterwheel is completed, and wherein the key proceeds to descendfurther in order to complete the movement of the type-bar to the platen,and also in order to complete the initial movement of thecarriage-feeding mechanism, is that there is considerable movement ofthe key possible at the lower portion of the stroke after themasterwheel has turned and after the full-stroke rack has ceased tofunction. Machines of this class are subject to a rebounding action ofthe type from the platen, and this rebound can occur in theabove-described play of the key below the range of action of thefull-stroke device. Due to such rebound and such play, the mechanism ofthe carriage is apt to be operated again, thereby causing a seriouserror in the calculation.

The present improvements aim to render the full-stroke rack effectivefor practically the entire descent of the key, so that the rebound ofthe type-bar and key cannot occur, or is at least so diminished that thecarriage-escapement mechanism cannot make a false additional operation.In order to secure this full control by the fullstroke rack, the latteris rendered micrometrically adjustable, so that it can be renderedeffective to the utmost possible extent, and so that thereafter thereshould be only enough left of the final portion of the key-stroke toenable it to reverse the action of the full-stroke pawl. This closeadjustment of the full-stroke rack is effected by a micrometeradjustment which may be common to all the racks.

Novel means for supporting the full-stroke rack are devised to reducemanufacturing costs, and are thus of advantage where a full bank ofnumeral-keys and a corresponding number of racks are employed. To thisend, there is provided a punched plate which may span the lower portionof the typewriter-frame to underlie the numeralkey-levers, said platebeing provided with punched apertures into which the lower ends of theaforesaid racks may be inserted, said lower ends in the illustrated formherein shown being provided with a shoulder to abut the top of saidplate, and also being provided with a hole through which, when the rackis inserted, there may be threaded a removable pin to abut the lowerside of the plate, said shoulder and pin thus co-operating to keep therack in place.

The rack-carrying plate with the upstanding racks therein is attached tothe typewriter-frame in a manner to permit fine up-and-down adjustmentof said plate and hence of the racks, said adjustment being efiective toset the racks relatively to the key-lever strokes; it being understoodthat the pawls which coact with the racks are pivoted on the key-levers.

Means preferably in the form of a grooved roll or stud are carried byeach key-lever to guide the associated rack at its upper ends againstdisplacement relatively to the pawl. Sufficient looseness in theconnection of the lower end of the rack to the supporting plate may beprovided for, the upper portion of the upstanding rack being thus ableto float about a longitudinal axis of the rack. Hence, even though theguiding means are used to prevent relative displacement of the pawl andrack, binding between the keylever and rack during the key-lever strokesis avoided. This feature is conducive to economy in manufacture,inasmuch as the necessity for close tolerances in machining andassembling the parts is avoided.

Other features and advantages will hereinafter appear.

In the accompanying drawing,

Figure 1 is a view of a cross-section of the typewriting machineshowing, in side elevation, the type-action, the computing register andthe arrangement of the novel full-stroke device. Said view may beconsidered as representing a row of numeral-key levers.

Figure 2 is a partial perspective, looking at the front of thetypewriter from the left side, and

brings out details of the full-stroke device, not apparent in Figure 1.

Figure 3 is a side elevation similar to the lower right portion ofFigure l and illustrates the fullstroke device with the key-leverdepressed.

;swing and print against a platen 17. Spri gs 11 return the parts tonormal position in which the type-bars 16 rest on pad 12. Saidkey-levers 11 are spaced and guided near their forward ends by the usualslotted plate 35 attached to the typewriter-frame 13.

The usual letter-feeding carriage for said platen 17 is represented byan extension 18, to which is attached a computing register 19, which, inthe carriage-travel, overrides a stationary actuator 20, connected tosaid numeral-key-levers by links 21, said register, actuator andkey-levers co-operating in a well-known manner, to the end that whenevera numeral-key is operated in a column of a computing zone of thecarriagetravel, a corresponding register-wheel 22 is rotated'to anextent corresponding to the value of the numeral-key. In order that saidregisterwheel 22 may register accurately, it is necessary that thenumeral-key be operated to the full extent of its down and reversestrokes, proper operation of the usual value-translating devices (notshown), associated with the actuator 20, depending on the completion ofsaid strokes, and also depending on the prevention of any untimelyreverse movement of the key-lever during the operative portions of saidstrokes.

The novel mechanism whereby full-stroke. movements and the prevention ofuntimely reversals of such movements are assured, will now be described.

For co-operation with a full-stroke pawl 23, pivoted and retained on anumeral-keylever 11, by a headed pivot-stud 24, there is provided afull-stroke rack 25, there being a plurality of pawls and racks, so thatthere is one pawl and one rack for each numeral-key-lever. Said racksare held stationary relatively to the up-and-down key-lever strokes bymeans to be described in detail later on. Each rack 25 has alongitudinal' edge extending in the direction of key-lever strokes, onwhich edge are formed two series of teeth 26, 27. The upper series ofteeth 26 may. engage an upper arm 28 of the pawl 23 to check,

ward movement of said key-lever when the key lever stroke is upward, thepawl 23 being shiftable about its pivot-stud 24, so that either of arms28, 29 may engage the corresponding series of teeth, it being understoodthat while one arm is engaged with its series of teeth, the other arm isnot so engaged. The shifting of the pawl oc curs at the ends of thekey-lever strokes, and is effected by means of a single two-way V-cam30, formed between and separating the two series of teeth 26, 27. Thepeak of said cam 30 projects suificiently beyond the tops of therack-teeth to secure an adequate extent of shifting movement of thepawl.

pivot-stud 32. Said detent-lever' 31 has a V- shaped nose 33, the sidesof which may override and engage the sides of a corresponding V-shapedarm 34 of the pawl 23.

The nose 33 of the detent-lever 31 is caused to be spring-pressedagainst the V shaped pawl-arm 34 of the pawl by means of a spring 36,which may be anchored at one end to a stud 37 of the keylever, the otherend of said spring 36 being attached to and pulling on an arm 38 of thedetentlever 31. Figure 1 shows in full lines the keylever and itsattached pawl and detent-lever in normal position, in which, as shown bysuch full A detent-lever 31 for the pawl is pivoted and retained on thekey-lever by a headed,

tached pawl and detent-lever, in which position the lower arm 29 of thepawl is seen to be engaged with the lower series of rack-teeth 27. Itwill be seen in the normal or full-line position, Figure 1, of saidkey-lever that the upper side of the detent-lever V-shaped nose 33presses against the lower side of the V-shaped pawl-arm 34, therebycausing, through the tension of the spring 36, the upper arm 28 of thepawl to be pressed against the upper series of rack-teeth 26. In asimilar manner, it may be seen, in the broken line or depressed positionof said key-lever 11, Figure 1, that the lower arm 29 is caused to pressagainst the lower series of teeth 2'7, the lower edge of the V-shapednose 33 in this instance pressing against the upper edge of the V-shapedpawlarm 34. Thus, during the downward key-movement, the tip of the upperpawl-arm 28 clicks or trails idly over the upper series of teeth 26, thelower pawl-arm 29 during said downward keymovement being totallydisengaged from its series of teeth 27. It will similarly be seen thatduring an upward movement of a key-lever 11, the tip of the lowerpawl-arm 29 will click or trail idly over the lower series of teeth 27,the upper arm 28 being in this instance totally disengaged from itscorresponding series of teeth 26. To ensure that the tips of thepawl-arms 28, 29 may not escape from their respective rack-teeth 26, 27,when an untimely reverse movement of the key-lever stroke is to beprevented, said teeth are preferably made of saw-tooth form. As viewedin profile, it will be seen that the form of one series of teeth 26 isreverse with respect to the other series of teeth 27. In each series ofteeth, therefore, the tip of the corresponding pawl-arm may be engagedby a tooth-edge that is so inclined relatively to the pawl-pivot thatwhen the pawl-arm and tooth-series are in contact, said pawl-arm, in anyattempt at untimely reversal of the key-stroke, is forced toward therack-teeth and cannot escape therefrom, and said untimely reversal ispositively prevented. It will also be seen that the teeth in each seriesmay be cut with any requisite degree of spacing best suited to insureproper operation of the register 19 and its actuator 20.

Figure 3 shows how the cam 30, forming part of rack 25, efiects shiftingof the pawl 23, said Figure 3 illustrating the instance in which thekey-lever 11 is just about to complete its downward stroke. It will beseen from said Figure 3 that just before the key-lever completes saiddownward stroke, the peak of the V-shaped pawlarm 34 is just overridingthe point of the V- shaped detent-lever nose 33, the pawl 23 having beencaused to rotate counterclockwise as the upper pawl-arm is engaged anddisplaced by the rack-cam toward the end of the downward key-leverstroke. Completion of said downward key-lever stroke to the positionindicated by the broken outline 40 of the key (Figure 3) will cause afurther displacement of the upper pawl-arm 28 of the rack-cam 30, andhence further counterclockwise rotation of the pawl 23 about its pivot.This rotation of the pawl is extended by the pull of the spring 36 asthe point of the V-shaped pawl-arm 34 passes the point of the V-shapeddetent lever nose 33, so that, as shown by the broken-line position inFigure 1, the upper pawlarm 28 is caused to be fully separated from theteeth of the rack-cam 30 when the key-stroke is completed, the lowerpawl-arm 29 being then in engagement with the lower series of teeth 2'7.In a similar manner, near the end ,of the upper key stroke, the lowerarm 29 of the pawl is engaged and displaced by the rack-cam 30 with aconsequent clockwise rotation or shifting of the pawl 23, so that itfinally assumes the position shown by the full lines in Figure l, and inwhich position it will be seen that the lower arm 29 s ful y paratedfrom the lower series of teeth 27 and that the upper pawl-arm 28 is thenin engagement with the upper series of teeth 26.

For holding the racks 25 stationary relatively to the direction ofkey-lever strokes, there is provided a simple elongate plate 41extending lengthwise from one side of the typewriter-frame to the otherand underlying the key-levers. Said plate may be stiffened by turning upits edge, as seen at 42. The plate is provided with rectangular punchedapertures 43, spaced like the key-levers 11, into which apertures thelower ends of the racks may be inserted, each rack being provided with ashoulder 44 to abut the top surface of the plate 41, and being furtherprovided with a hole through which there may be threaded a removablecotter-pin 45, said shoulder and pin keeping the rack in place in theplate 41.

For free action of the key-levers, the sides of the upper portions ofthe racks are spaced slightly from the sides of the key-levers, and, tothis end, each key-lever has projecting therefrom a grooved stud or roll46, which, as seen in Figure 2, spaces the side of the upperrack-portion from the key-lever.

It will be apparent that any one of the racks 25 may be removed easilyfrom the machine when its cotter-pin 45 is removed. To withdraw a rack,the best procedure is to raise the rack until its lower end clears thetop of the plate 41 and then to bring said end forwardly to clear theplate 41 sufficiently to eifect downward withdrawal of the rack. Thegroove in said stud or roll 46 embraces a front edge 47 of the rack,said front edge 4'? bearing against the bottom of the groove, and thuspreventing excessive forward and rearward displacement of the rack 25. Aslight forward and rearward displacement of said rack is permissible,yet may be avoided by curving the rack-edge 47 to conform to theslightly arced path in which the grooved roll 46 moves. The arcing ofthis path is so slight, however, that in the illustrated form of theinvention, said rackedge 4'7 is shown as being straight. The connecetion of the lower ends of the racks with the plate 41 may be ofsufiicient looseness to permit the upper end of each rack to float aboutthe vertical axis of said rack. Sufficient floating movement may thus beobtained, without any undue up-and-down play of the racks, and isconducive to free action of the key-levers during their proper operatingstrokes. This floating movement is also conducive to braking thekey-lever against an untimely reversal of the key-stroke because, asalready explained, when such an untimely reversal is attempted theactive pawl-arm 28 or 29 is forced against the rack 25 which in turn isforced against the bottom of the groove in the roll or stud 46 tothereby afford a corresponding measure of braking effect upon thekey-lever.

The initial and final positions of the keylevers are liable tovariation, due to assembling adjustments of the type-action, and toaccommodate such variation the plate 41 is provided with an up-and-downadjustment, so that the upstanding of said lug 48.

racks 25 in said plate may also be adjusted up and down. As alreadyexplained, the plate extends from side to side of the typewriter-frame,which, for attachment of said plate, may be provided with lugs 48. Theends oi the plates may be provided with downwardly-extending screwstems50 having flanges 51 affording a broad bearing of said screw-stems 50against the plate 41, in which the upper portions of said screwstems maybe riveted, as indicated in Figure 2. The screw-stems 50 pass throughclearance holes in the typewriter-frame lugs 48, and each stem hasthreaded thereon adjusting nuts 53, 54, the nut 53 being for abutmentagainst the upper surface of the typewriter-frame ing 48, and the nut 54being for abutment against the bottom surface It will be seen now thatmanipulation of the nuts 53, 54 may effect raising or lowering of theplate 41, and consequently raising or lowering of the racks 25 foradjustment of said racks relatively to the key-strokes. By means of thescrew-jack-device 50, 53, 54 the instant at which the detent 31 snapsthe pawl 23 into reversed position may be finely timed. The rack-unit25, 42 is also easily and quickly adapted to variations which may obtainas between diiferent machines in respect to the spacing of the abutmentsor lugs 48 below the key-levers. The fine timing of pawl reversal may beso correlated to the operation of the usual carriage-feeding mechanism(not shown), operated by the usual heel 55 of the type-bar 16, that thefault of repeated printing is avoided.

Variations may be resorted to within the scope of the invention, andportions of the improvements may be used without others.

Having thus described my invention, I claim:

1. In a typewriting machine having frame side members, the combinationwith a row of laterallyspaced key-levers supported bet-ween said sidemembers, of full-stroke devices including fullstroke racks, one for eachkey-lever, each rack adjacent its key-lever and extending in thedirection of key-stroke, and a rack-supporting bridge attached to saidframe side members, said racks being attached at their lower ends tosaid bridge and spaced therein according to the key-lever spacing, saidbridge being spaced from and underlying said key-levers transversely.

2. In a typewriting machine having frame side members, the combinationwith a row of laterallyspaced key-levers supported between said frameside members, of full-stroke devices including full-stroke racks, onefor each key-lever, each rack adjacent its key-lever and extending inthe direction of key-stroke, a rack-supporting bridge spaced below andextending transversely of said key-levers, said racks being attached attheir lower ends to said bridge to form a unit, and

spaced therein according to the key-lever spacing,

and means for attaching said bridge at its end to said frame sidemembers, said means including devices arranged for micrometricadjustment of the bridge toward or from the key-levers, to finely adjustthe position of the racks to the key-lever stroke.

'3. In a typewriting machine, the combination with a row ofnumeral-keys, of a full-stroke device including a plurality of two-armedpawls, one for each key, and pivoted thereon, the pawl-arms extendingfrom opposite sides of the pivot substantially in the direction ofkey-strokes, a corresponding plurality of full-stroke racks, a commonmounting member for said racks, and micrometric adjusting means engagingsaid member at two spaced points and thereby effective to finely adjustthe row of racks in parallelism with the pawls and also in the directionof key-strokes, each rack having. formed thereon a pawl-shifting cam.

4. The combination with a reciprocatory keyoperated member, of a pawlpivoted on said member, said pawl having two arms extending to oppositesides of the pawl-pivot substantially in the direction of themember-strokes, said pawl being shiftable to call one arm or the otherinto action, a full-stroke rack for co-operatio-n with said pawl, saidrack having two spaced series of pawl-engaging teeth for engagement withrespective pawl-arms, and also having a pawl-shifting cam formed betweenthe two series of teeth and effective for engaging and displacing one orthe other pawl-arm to shift said pawl at the ends of the reciprocalmember-strokes, and means arranged for micrometrically adjusting saidrack in the direction of said strokes for closely adjusting the shift ofthe pawl by said cam.

5. The combination with a reciprocatory keyoperated member, of a pawlpivoted on said member, said pawl having two arms extending to oppositesides of the pawl-pivot substantially in the direction of themember-strokes, said pawl being shiftable to call one arm or the otherinto action,

a full-stroke rack for co-operation with said pawl, said rack having apawl-shifting cam effective to shift said pawl at the ends of thereciprocal member-strokes, a detent device carried by said keyoperatedmember and operative to snap the pawl to position after a partial shiftof the pawl by said cam, and means arranged for micrometricallyadjusting said rack in the direction of said strokes for closelyadjusting the instant at which said pawl is snapped to position by saiddetent.

6. In a typewriting machine, the combination with a key-lever having ahorizontal arm extending transversely of the key-stroke direction, of afull-stroke device including a shiftable full-stroke pawl pivoted onsaid key-lever arm, a full-stroke rack for co-operation with said pawl,said keylever arm having a rack-guide spaced from said pawl andeffective to retain one end of said rack in position for co-operationwith said pawl, said rack being extended in key-stroke direction to apoint substantially below said pawl and guide, and a mounting arrangedbelow said key-lever arm, for holding said rack stationary relatively tothe direction of key-stroke, said mounting having an opening arranged toreceive the lower end of said rack, said lower rack-end having ashoulder abutting a face of said mounting and a removable key abuttingthe opposite face of the mounting, whereby said rack is rendered readilyremovable from and replaceable in said mounting.

'7. In a typewriting machine having a frame, the combination with akey-lever having a horizontal arm extending transversely of thekey-stroke direction, of a full stroke device including a shif ablefull-stroke pawl pivoted on said key-lever arm, a full-stroke rack forco-operation with said pawl, said key-lever arm having a rack-guidespaced from said pawl and effective to retain one end of said rack inposition for co-operation with said pawl, said rack being extended inkey-stroke direction to a point substantially below said pawl and guide,a mounting arranged below said keylever arm to receive the lower end ofthe rack, and means attaching said mounting to said frame, said meansbeing micrometically adjustable to adjust the elevation of said mountingto compensate for variations in the frames of different machines.

8. In a typewriting machine having frame side members, the combinationwith a row of key-levers having horizontal arms extending transverselyof the key-stroke direction, of a corresponding row of full-strokeracks, a plurality of full-stroke pawls, one for each key-lever andpivoted on the horizontal arm thereof, each key-lever having guidingmeans spaced from said pawl and effective to retain one end of acorresponding rack in cooperative relation to the pawl, arack-supporting bar extending transversely of and substantially belowthe key-lever arms, said bar arranged to support said racks inupstanding position, and abutments on said frame side members arrangedfor securing and supporting said bar, at its ends, below the key-leversas aforesaid, and for inserting and removing said unit by way of thebottom of the machine.

9. In a typewriting machine having frame side members, the combinationwith a row of key-levers having horizontal arms extending transverselyof the key-stroke direction, of a corresponding row of full-strokeracks, a plurality of full-stroke pavvls, one for each key-lever andpivoted on the horizontal arm thereof, each rack having a pawlreversingcam, a rack-supporting bar extending transversely of and substantiallybelow the keylever arms, said bar arranged to support said racks inupstanding position, abutments on said side members for supporting saidbar, at its ends, below the key-levers as aforesaid, and a screw-jackdevice between each bar-end and its abutment, the screw-iack-devicesbeing arranged for securing the bar to said abutments and formicrometrically adjusting the same up or down for proper operation ofthe pawl-reversing cams.

HENRY L. PITMAN.

